Not without modification. Check the Pina book, he covers the conversion from the 400K to 800K bracket, which shows the differences, but the reverse should also workable, if you cut into it to allow for the rear gears (not as simple as drilling a few new holes). You are probably better off trying to obtain the correct bracket though.
Here are tworeasonably priced items on ebay now. But depending on how fast you are planning to add these, you might well be better off buying a whole stock 512K, by the time you pay for a 512K logicboard with 64K ROMs and a 400K drive and bracket. FWIW, I've never seen 64K ROMs sold by themselves on eBay.