There aren’t many good monoculars out there.
IMHO the Tasco’s are OK for a quick peek at something (and I have a couple), but at about $20 each, you not going to get much and you shouldn’t expect to. Also, their extremely short eye relief gives me problems since I wear glasses.
I have a 5 X 10 Zeiss monocular which I really like, but I’m pretty sure it’s smaller than what you want. It’s about the size of a fat fountain pen and obviously that 10 MM objective doesn’t gather much light.
I’ve never used the larger Zeiss monoculars, but they do seem awfully expensive for what you get.
Incidentally, I just got a small 10 X 25 Minox roofprism binocular from SWFA, which I’m very happy with (though it is apparently missing two of the four lens caps).
These retail for about $150. SWFA has dealer samples for $99 at [url]www.samplelist.com/[/url], which is what I got (hence the missing lens caps). For the price, it is excellent.
Note that they just changed the above website and it is confusing. If you decide to check it out, do not click the “manufacturer” button or you’ll only get 10 selections. Rather, click the “binoculars” button.