Eppie, the M14 went into service 4 years after the Korean war ended, the relic you are thinking of must me the excellent M1 Garand.
allaroundhunter, those bullpup conversion kits are pretty slick. There are two kits available, BullDog 7.62 and the Rogue.
This was my Rogue with an 18" barrel.
The piston driven M14/M1A is probably the all around best 7.62/3.08 battle rifle design available.
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