I would suggest Daley's - get the grafted ones please not the seedlings

Yes - pricey but Turner's also have Jaks but I'm not so sure they have more varieties.
A little scrimping here and there to be able to buy a grafted Daley's jak or two is a good start.
Just take good care of your Daley's potted tree then later on, get scions and graft onto your seedlings.
I do not have a lot of experience grafting plants that bleed latex - but some good threads in here about Artocarpus grafts and members are pretty nice overall so don't be afraid to ask the more experienced ones for advice.