I asked this previously, but I don't recall the answer, so if someone could help me again, it would be greatly appreciated.

I have an Astro-Tech 66ED doublet that I am quite pleased with overall. The color correction is very good for doublet, but it's not perfect. I currently use a 2" SCT-style di-electric mirror diagonal, because I enjoy low-power wide-field views of the Milky Way, clusters, occultations, etc. (the strength of this scope, IMO). To this end, I have a 2" widefield eyepiece that gives me 5+ degrees of sky at 15x. I also have some RKE and UO orthoscopic eyepieces that I use for general purpose observing. Since the 2" diagonal threads-on, it's a minor pain to install and remove it just for the sake of using a smaller diagonal. Ideally, I'd like to have a 2" 90-degree prism diagonal - so I can enjoy the benefits of the increased correction for higher power planetary/lunar viewing, and still be able to use my 2" eyepiece for low power views without swapping out diagonals.

So, where can I find a 2" 90-degree prism diagonal? (preferably one that doesn't cost several hundred dollars)

Regards and clear skies,

MikeG