Go a mild cam with not too much lift.
A set of flat top pistons and 1-2 mm over size bore.
Downdraft weber
Extractors
Oval port head (h89/75)
Lightened flywheel
Have everything balanced to complete it.
It all depends on how much you'd like to spend... At the end of the day the sky's the limit but each of the above mentioned should make for a nice little package. Currently I'm pretty much running that an it's a really nice mild street/ daily package...