I like the fruity taste of habanero a lot (the red ones if that matters). But I usually get stomach pains after eating them (not that it stops me). Are there any chilis that taste similar to habanero but burns less/are easier on the stomach/have less scoville rating?
If you love the tangy, fruitiness of habanero (Scotch bonnet) peppers but can't handle heat, I have some news for you. Trinidad Perfume's golden fruits have traded gut-wrenching fire for an incredibly flavourful, aromatic citrusiness [sic]. Being sweet and with barely any capsaicin, this is the ultimate chilli-hater's chilli.
p190. Grow for Flavour, James Wong. 2015 Mitchell Beazley
As to where one might find them - I suppose that mainly depends on your physical location. To be honest, I haven't seen them for sale around here (London).
Googling does provide a rather large number of options to buy seeds and even grown plants.
Allepo pepper has a fair bit of fruitiness, but it's typically only available dried in most areas, not fresh. And I suspect it may be harder to get these days with the conflict in the area where it's grown.
What you can do, however, is change how you use habanero peppers.
Add them whole to recipes and remove them before serving. As the capsaicin is mostly on the inside, you'll get some of the fruitness, without the full hit from the heat. If you want a little more heat, stab it with a knife before adding it (but don't cut it open fully).
One of my former co-workers made groundnut soup this way, and it had great flavor without knocking people out. (I think he had 3 or 4 in there; I don't know if they were punctured or not)