I went to the 'Recruits' game convention in Lee's Summit, Missouri two weeks ago in order to run my Arena of Blood game. They have a silent auction each year, and this year's auction offered a lot of items. I managed to snag a cardstock Imperial Firebase for $10, in superb condition. The previous owner had sprayed the bulkheads black and painted them blue- pretty vibrant- but it wasn't too far off the saturated blue of the printed bits. I decided to base it into three separate elements, painted the edges of the card pieces, and weathered the bulkheads to blend them in a little more, matching the rust effects on the printed card. Considering this is card terrain I'm pretty happy with the end result.
I'll probably be giving an old beat up Imperial Bastion I have the same treatment, and I'll take a look at my old Necromunda stuff while I'm at it. I never wanted to permanently base it, but it would certainly tie it in to my existing industrial layout and probably preserve the condition too.