Spotting scopes, telescope eyepieces

I have a Meade EXT90, which I adore for terrestrial and astronomical viewing, however it is of course not waterproof, nor rugged.  Presently my son has it, as he and his wife are messing around with using it as a lens for their DSLRs.  I doubt I will get it back 

I need a spotting scope that I can backpack with to use for hunting, range observation, terrestrial observation, birding, and astronomy.  I have zero interest in zoom eye pieces, given that, generally speaking, less lens elements in fixed power eyepieces result in clearer pictures (I am not able to particulate in the Swaro/Zeiss/Leica range of economics, where zoom eyepieces aren't so bad).

I happened to stumble upon the Pentax PF-80ED.  Several reviewers at the jungle store indicated using eyepieces with this scope whose brands are generally associated with the astronomical community.

That got me thinking.  I know many brands offer spotters with removable and interchangeable eyepieces.  But do they all share a standardized size and attachment system?  Pretty much any astronomical telescope can share eyepieces, given proper barrel size, or an adapter.  Thus, with my Meade, I had eyepieces from a half dozen different brands, and in various configurations.

Does a similar shared standard exist with sporting spotting scopes?  

If not, are there any companies specifically making spotters with this capability (perhaps like the Pentax above)?

Are there any "gotchas" associated with the use of astronomically-minded eyepieces with sporting scopes?

And if there are spotters that can use varied eyepieces, do any of you have experience with brands and models?  Looking for ED/HD/APO glass at a minimum, price range in the $800-1200 area for a combined scope body/initial eyepiece purchase.

Thanks.