Source for high strength Optical Lenses

I am very near sighted. I had a MARES ESA Mask which I picked because I could get 'off the shelf' -10 lenses. Unfortunately, I dropped the mask and, although the lenses were intact one of the hard plastic parts of the mask broke and I can't find replacement parts. I don't get to go out much so I want to minimize my expense on a replacement mask. I have found -8 lenses, but nothing stronger than that. Does anyone know of a source I can order something stronger than a -8 from without the expense of getting something custom made.

Thanks for the help.

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Welcome to Prescription Dive Masks 1-800-538-2878.

I wear about -9.5 in each eye, so I know what you're talking about regarding the difficulty of finding high-prescription correction at a reasonable cost. I've got an older CressiSub Look mask that I got in Europe with my correction, but that's not available here in the States.

I've just been looking for a spare mask with an appropriate correction.

Custom lenses are likely to be rather expensive. I've also got moderate astigmatism, but spherical correction has always worked just fine for me underwater.

One possibility would be a Mares Opera mask. It's also discontinued, but may still be available in some places... the corrective lenses can still be found too, and are/were available in up to -10.0.

What I finally got was the Edge Vision mask, available from Divers Supply.com:
Edge Vision Mask with Optical Lenses @ Divers-Supply.com.
It's available with corrective lenses already installed, up to -10.0. Can't beat the total price of about $90.

Haven't dived with it yet, but the quality appears to be decent. Not marked as to where it's made, but I'd suspect China. The black silicone skirt I got is nice and soft, and seems to fit me very well. The U.S. company, Edge, has a sub-forum here, and have gotten some nice comments from members.

Thanks to everyone for the comments. While I was waiting for a reply, I tried out one of the ScubaBoard's advertisers (101 snorkel) and they also have -10 lenses. I am not sure if I will pick the Edge that Marek K mentions or the one from 101 snorkel. Since I only get to go snorkeling a few times every 18 months or so when I get to go on vacation, I am content with something that keeps the water out and I can see through. If I was able to go more often I would invest more. Thanks again.