The Frederick is a fine looking hat!I think I've found my new primary source for hats! I spoke with Ernest DelMonico who was very helpful and informative. He told me that Long Oval just isn't being made anymore, but that DelMonico does their own blocking, and to just specify that on the order form. I decided to give them a try, so I ordered an inexpensive Stetson Reward Shantung Fedora with the request to block it to 7-1/4 LO.
He also said that it's not necessary to shape a fabric hat or cap to the long oval size. Because caps and fabric hats are softer, and not fixed in their shape, they will naturally mold themselves to a long oval head. He also advised me (and I guess anyone wearing a LO) to stick with proper sizes (7-1/4, 58cm) and avoid the S, M, L, XL hats. Given the variances I've seen with the generic sizes, I think that's good advice (also knowing that variances can occur even among the 'proper' sizes).
And DelMonico has a great selection of hats! A feature I also noticed was the "trigger" notice when a hat is out of stock. The wording is, "NOTE: The product you have selected is currently out of stock. Adding it to basket will trigger a PRE-ORDER of this item.." with an estimated ship date. I have my eye on such, a Stetson Frederick Wool Felt Fedora in navy blue. When I receive my first hat, I'll judge whether I want to go ahead with the Frederick.