JPM heads can be bought from stock like that, 4inch bore.
LN engineer nicasils can be custom made, extra cost is 250 dollars, but if dollar to euro rate stays as low as it's now, nickies wont be so expensive. Ok, still quite expensive
But possibly big improvement on a big bore engine.
At the moment mendeola suspension, bodywork and 915 transmission which is still on a shopping list, have made my wallet almost empty, so i have to wait until next year to buy these engine parts