Vintage 1970's (I think) Jap optics 4 x 20 scope, very good condition, gloss, comes with rings, £30 posted. Tried it on my MK3 and it looked good, nice light scope which shouldn't put too much strain on the MK3's rail. Obviously can be used on any gun. Pictures below....

https://flic.kr/p/S1QW43
https://flic.kr/p/2cL2X3T
https://flic.kr/p/S1QVVN