Alstar Red Dot Finderscope for Telescope Deluxe Finder - Metal Star Pointer Viewfinder Astronomical Telescope Accessories with Dovetail Finder Bracket

Fantastic! That diagonal upgrade is one of the first three improvements that crossed my mind before I ever got my hands on that refractor. Along with a better diagonal, you might eventually want an affordable all metal red dot finder like this one, unless you are more partial to RACI finders or larger reflex units such as the Telrad or Rigel. You may also find yourself upgrading the tripod even if the supplied AltAz mount handles the SV520 reasonably well. If it resembles the related SV225 and SV225 Mini mounts, then the head itself is probably better than the included tripod suggests. In other words, the mount may become noticeably steadier when placed on a more substantial tripod than the serviceable but weakest-link tripod supplied by Svbony.