Wow. Sounds like you hit the jackpot. You can find them online but they are always high. I will buy up un-restorable planes for parts and I sometimes will come across another tool fanatic’s parts stash in an estate sale. There were lot of Stanley clones produced after the original patents ran out and many of the parts are interchangeable. I have already looked through my parts for a mouth adjuster for that block plane of yours with no luck. I may have a part or two in the pile if you will send me a list.