I just took a similar plunge; moved from 4" to 8" long bed. My primary shop is almost totally WWII era Delta(Milwaukee), and I really lucked out on an 8" jointer that matches. The previous owner had replaced the original belt with a link belt, put the jointer on a modern mobile base(which, despite it's lack of authenticity, is pretty f-in awesome), and new knives for the cutterhead. The only issue is a crack in the porkchop, which is off to a local smith for repair right now. All told, I paid 325 dollars, which is NOT what anyone should expect. I'm not gloating, but rather, trying I make a point: whether you prefer old or new tools, if you have the opportunity to exercise patience, there are amazing deals to be had. Unfortunately, the woodworking industry has taken a big hit, shutting down large furniture and cabinetry shops across the board. I am not saying that you should be a vulture and try to profit from the suffering of others, but there is something to be said for "right place, right time". Watch the auction houses, sites, classifieds, and scrapyards(yes, scrapyards; these bigger machines get scrapped ALL THE TIME, because they're so big, and people don't want to deal with them), and check out EVERYTHING that looks promising. You never know what you may find. Good luck to you, and don't be scared of older machines!
WCT