The recoil on Desert Eagles isn't as bad as most revolvers due to weight and the way the heavy slide deals with the shock.
The rail slot spacing isn't true picatinny, but width is normal enough to work with most anything. So you can't use one of those offset mounts like everyone used to put on their AR, as it spacing spans many slots.
As far as long term, I have used a couple of cheap pistol scopes and a couple of moderately more expensive with good results.
Here is an example of a cheap one... UTG, kind of big and heavy, but has survived the recoil anyway. Probably a bit too cheap, so could be hit or miss.
I use the classic Leopolds as were offered through Magnum Research for years as well. They are simple, but tough. I can't tell you the model numbers however. I bought a Nichols scope in the 90's also, and ran it on my 50AE for many years, thousands of rounds without issue. All of these classics I run are low power. (1x to 2x)
There should be a lot of people with a lot of experience and opinions with sighting systems for these guns... maybe they will stop by soon. :)
MrBlackCat