SHA 14:12 with a #53 jet will give you same performance but less leak/weeping fuel.
SHA 14:14 with a #56 jet will liven up the bike a little but you may have to ream out your shorty intake or upgrade to an intake for a SHA15:15. Some stock intakes are 12mm and some are 13mm you will need to measure to be sure.
Either of those two will get goodly performance, if you derestrict the stock exhause it will really freshen up the bike. Also adjust the timing to 1,5mm BTDC to get her moving nicely.
SHA 15:15 with a #62 jet will get your bike moving but you will need to upgrade to a 15mm intake and you will also need to derestrict the exhause. Best also to match port the intake to the cylinder.
The SHA15:15 is like the gateway drug of carbs and you will likely want to get a goodly pipe to go with it... and a after market variator... and...