Custom lamp shades?  

I'm pretty good at crafting stuff and have made some lampshades. I think they're a pain in the neck to do as well as store-bought ones, and you can end up paying nearly as much for decent materials as for a new shade. It's a good option for someone who wants to use a specific paper or fabric that isn't available commercially, but otherwise I would exhaust all other possibilities before going that route.
The last time I researched online custom shades, Fenchel Shades had the widest range of sizes and shapes and their prices were better than some other sites. (I used another site before finding Fenchel and the prices were high and the edge binding started coming unglued within a year. I don't remember what site it was, just that it was big and sold other lighting stuff too, i think.)
My daughter needed a tall cylindrical shade with a very small diameter, like 4" or 5". The height was at least 32", maybe even 40", i can't remember. The diameter was the smallest Fenchel offered; no one else at the time offered it. That was 3 years ago.

I've had several shade made during the year. I'm located in Chicago & I use Benko Lamps, LTD. Their customer service is divine- the shop is owned by a husband & wife probably for 40 years or more! Their pricing MAY be on par with your Blanche P. Field. I didn't use Fenchel because I wanted true customization (I provided my own fabric), consultation and input. If you're searching for a "simple" shade, I would use Fenchel. Mr. Benko would be happy to work with you, even if you're located out of state! The black shade is an octagon shape. The rectangular shades have custom, rounded corners. The leak lamp will be stained darker to compliment the shade!