Recommend me a converter for this 273 - 727 combo

I was thinking the same thing around 2200, but I know it can be a hard time trying to get converters for the small journal.

Can you explain this further, I dont quite understand. If we leave out that I will get a 360 in the future and then assume I have the stock crank on my 273 right now. Could I go with a converter that is advetrtised to fit my 727 trans?