XL100, XL125, XL175, XL185, XR200 should all be basically the same motor with different bore and stroke.
It is possible that the 175, 185, and 200 are taller overall, thus, the smaller ones may or may not mount up.
Also, CB100, CL100, CB125S, CL125, SL100, SL125 all are basically the same motor as the same-displacement XL models.
Honda ATC 3-wheelers in this size range are likely good candidates too, but, may have pull start instead of kick-start.
There is a 200 CC Lifan motor which is a clone of this series of motors. It should fit too.