Kanter Auto Products
has them too. The basic kit costs $1,100 (item #089749G).
I suggest you get with a GOOD engine machine shop, and decide how far you will bore and hone your cylinders.
After you order and get delivery of your new pistons, the machine shop needs their diameter to do the actual boring and honing.
You can find good stuff on eBay, like true roller timing chains and Clevite 77 bearings. I suggest you pop for moly rings. All the new engines use them. That's one reason why modern engines last so long.
Head machining is a must. I had my exhaust valves machined and fitted with hardened seats, and I had the stem towers machined for viton seals. The hardened seats will allow safe use of unleaded gas, and the viton seals work a whole lot better than those umbrella seals (that harden and fail). - Dave