are you suggesting that there are fake copies of pistons / rings / shells etc around?

I'm only familiar with chinese 'copies' of conrods of which i have used 2 sets both to 7700 without any problems. for about £200 a set they were perfectly machined, balanced and came with new arp bolts (the bolts were indistinguishable from genuine arp ones so i think they are genuine!). they compared favourably with arrows rods costing 4 times as much.

by contrast you could you could overhaul the stock rods by fitting new little ends / hone the big ends / buy new bolts etc and spend nearly as much then you finish up with 30 year old rods which imo is a bigger gamble than the chinese ones. for some reason the genuine rods seem to fetch crazy money on ebay so you can get most of your £200 investment back.