The telescope manufacturer William Optics offers very high-quality apochromatic and achromatic refractors which are very well suited to visual observation, and especially to astrophotography.
William Optics
Expandable 1:10 Micro gear for Synta focuser
$ 225.00
ready for shipping in 24
h
William Optics
Adaptors for EAF focus motor
$ 391.00
ready for shipping in 3-5
weeks