If you look at the right side of the amp control panel is a name. It appears to be Electra 2570. Right click and save the picture to your PC. Since it is a eBay it will create a subdirectory with lots of images in it. Find the pic of the front of the amp and click on it. Use the Microsoft software to zoom in. You should be able to read the model name and number. To me looks to be a Electra 2570 and seller should have typed 2 x 10" speakers. It seems to match rest of description.
I'd say Alamo amps are generally undervalued and probably worth more than current selling price. Especially since Alamo did OEM manufacturing for other brands just like Danelectro and Valco. Also Alamo was one of the oldest guitar amp companies and involved with supplying some historically significant brand like Aloha. I think even the Texan company location makes it collectable. They made lots of models so pays to ID the more interesting models. Sort of the same to sorting through Silvertone, Airline, Valco, Supro and Danelectro stuff. Alamo is just early days and collectors haven't tapped into it yet.
Young players could use Alamo to create some new alternative Southern genre (as people have done with Supro and so on).
If you get this Electra 2570 make sure you do a conversion to 3-wire power cord and swap the electrolytic and filter caps if all that hasn't been done before. It might have a "death cap," which if there will need to be removed. Clean and lube the potentiometers. Also mind usual high-voltage / milliamps safety precautions!
Yes a Blackface from 1961. Alamo was Blackface before Fender!