340 main caps

You wil have to find a good rear main cap from somewhere. (these can come from a 318 as they are the same but 318 forward caps are shorter.) The others can be bought aftermarket from places, like ProGram, and fitted. If you get used factory replacements or aftermarket they will need to be fitted and line bored which can be pretty expensive. If the block is still standard bore or has numbers you need it might possibly be worth it but you need to figure in additional costs for getting it in condition to use.