I have in the past worn immense frames also, and when I first started
looking for cheaper alternatives online was unable to find the *really
big* frames I was used to wearing. The ones that make me look like a
90 year old senior citizen from Miami, in retrospect.
The different sites have various ways of narrowing things down. With
Zenni, for example, look at how they state the mesurement in the frame
descriptions (eg., "Lens Width 51mm"). Paste that into the search
field and change the 51 to 55 and it will find all the glasses with a
lens width of 55mm. You can't narrow down the search results, but you
can get things to a manageable group. Searching on "Temple Arm Length
140mm" found these, for example:
http://www.zennioptical.com/cart/product.php?productid=451&cat=0&page=1
which seem to meet your criteria.
Other sites have different tools (or no tools). Optical4less lets you
choose a frame material, then filter the results by various dimensions
(lens width, bridge width, etc.). Goggled4u Lets you search by a large
array of parameters, including dimensions, material, color, etc.
But you're right showing a single frame in a variety of sizes is not
usual with online opticians. Rather, each frame in its unique size is
shown as a separate item on most sites, although sometimes the same
frame in different sizes is actually available - it's just that each
size is its own catalog number or SKU, so you often don't realize that
they're the same style.
As an aside, I have discovered that despite my giant Irish head, now
that I have less hair I think I look better with smaller frames, and
the low prices of these glasses let me buy multiple pairs of single-
vision specialty glasses instead of having one pair of giant Mr Magoos
for all occasions. I have single-vision computer glasses next to my
computers at home and at work. I have an attractive single-vision pair
for distance only that I wear when we go out to concerts or movies. My
favorites are the rimless titanium progressives I got from Zenni, that
are almost invisible on my face, rendering the whole "size" issue
moot. When I started wearing them people thought I'd gotten a face-
lift. :)