Glass and stainless can certainly be sanitized well enough to put back into general use. As far as any plastic or wood that contacts the sour beer, then no. I would buy a separate fermenter for the Flanders for two reasons. The first being that the beer will take from six to eighteen months to achieve its proper character, and the second is that those bugs seem to like things better in a wooden (oak) barrel. Small barrels made from American oak are probably best because American oak is less porous than French, so a small barrel would have less oxygen infiltration if made from American oak.
As far as priming and conditioning, probably not a good idea. I can see bottle bombs in your future.
Best of luck.

I think you would be fine with bottle conditioning sour beers provided they have a fairly low finishing gravity and the bugs have worked themselves out. Just be sure to let those beers sit for 1-2 yrs and check their gravities to be sure they are not dropping anymore. They are typically not overly carbonated beers anyway (well a gueuze is...). With that said, I have 20 gallons of sours going - flanders red, brown, and pale plus a lambic. I will probably keg one or two and bottle the others depending on when they are ready.

Ok, I'm pulling the trigger.
I'm going this weekend to buy the ingredients and a new plastic bucket. Hopefully, it will be brewed and happily bubbling away by next weekend.

OK, my turn to add to the thread.

I have a 5-gal oak barrel that is currently loaded with about 3 gal of port.
Recently, I made up about 9 gal of Oud Bruin "base" (recipe from BCS). OG is around 1.070 and fermentation is just about complete, although I haven't measured the FG. Used WLP001 for the primary fermentation.

In the VERY near future, I'm going to rack the port out of the barrel and fill it up with the Oud Bruin. I'll add my packet of Roselare blend.
Hopefully it'll turn out OK in a year.

Any pointers or suggestions?

One thing I have learned about pitching wild yeast (brett) and bugs (lacto, pedio) is that it is wiser to mash higher than average temps. This leaves lots of residual sugars for the bugs/yeast to sour and funk things up. For instance, if your beer finishes at 1012 with regular cal ale yeast, then you are really not leaving much for the bugs to do their thing. If you are finishing at 1018 or so, now you are giving those bugs a real chance to sour things the right way. That is my first tip.
Second tip, would be to give it a lot of time with a minimum of 1 yr and even better at 2 yrs. (depending on the style). After much reading I have gathered that letting the sour beers weather over the course of 2 summers seems to be the best. If you can wait that long.....
I usually start mine in a bucket, than rack them after a week or so, when fermentation just starts to slow. This method allows for most of the CO2 to be pushed out of the carboy, so you aren't left with a yr. old oxidized beer. A pellicle will sometimes (not always) form in the presence of oxygen (depending how much there is in there) in the headspace to protect your beer from too much oxidation occurring.

Great tips Brewinhard.

I think that I mashed around 152 (that's what I was trying for anyway), but there might have been some 'cooler' pockets. the last brew I did was "at" 152, but it finished at 1.008, so I'd bet that it was on the cooler side. You think that adding some lactose or other sugar for the wild beasties might help?
I am definitely planning on a year or so in the oak barrel. The idea is to get the wild bugs to make a nice new home so that when I do it again next year, I can keep the barrel wet with sour beers. Might throw some cherries in before bottling - but that will be a while.

You might consider adding some corn starch. The Brett can eat it but the Sacharomyces can't. The Brett will also eat the cellulose in the barrel walls.

4 months into my first use with Roselare. Pitched packet only into Flanders Red and after 7 days of fermentation, racked to a carboy with some oak. Finally starting to see some pellicle formation, even if it is just a dusting of brett on the surface. Already saw the weird lacto bubbles form. Thinking it took such a long time to form a pellicle due to racking while the beer was actively fermenting pushing all oxygen out of the carboy. I can't stand oxidized beers in any way!