Being that the crank must be pressed apart to replace the rod bearing and Invader cranks are relatively plentiful, most guys opt to swap in a good used crank rather than replacing a rod or inner crank bearing.
I am unsure about the Invader cranks, but last time I had crank work done on an Interceptor/LTD crank the rod bearings were not available. I would suggest contacting Jerome at Crankshaft Services to inquire.