I can supply seals for a lot of the crosman range inc ftp's and converting the valve front to a ft
I get my pump cups stems and checks from a UK supplier but the cups from the US are often the later type that fit the front of a valve better (p1377 model)
on a 13xx there is only 3 orings a tp seal check seal valve stem and pump cup
probe (varies on model)
valve inner same for all
valve outer same for all