Power head on 120XR2?

[X-17]

The power head has some serious damage. So the question is if a power head from an outboard can be used? It is a 1999 model, and there is an adapter plate between pump housing and power head. The gasket between power head and adapter plate looks like the attachment. I understand that I may have to fabricate an exhaust manifold "adapter". New powerheads are NLA, and used ones virtually nonexistent here. Outboards of all types however are easily available.

 

[X-17]

Further info:
1) Shaft from pump going into crankshaft of powerhead is approx 22.5
mm in diameter (that is 7/8 inch)
2) 13 splines

 

[X-17]

It appears that block was only used for the 120 sport jet. BUT the pump unit '99 on was used for both 120xr2 and 175xr2.