z1300 81 Model Connecting rod bearings

Are there any alternative Connecting rod bearings and crank case bearings one can use on the Z1300 81 Model ? Especially motor vehicle bearings as they are readily available.

I notice that Z1300de still have some sizes of the genuine bearing shells. Quite expensive though. I don't know about after market bearing shells for motorcycle engines. Perhaps a precision engineer could adapt some suitably sized automotive shells .
Good luck.