When a tube with an 800 watt dissipation costs $1,525, while the BLF188XR transistor is only $200 for 1,500 watts, you know tubes are a dying breed. While transistors require a lot more support circuitry for reliability, once it's intact, you don't have to replace them like tubes.
Both Econco and Eimac are struggling today. Econco can't buy duds for rebuilding from the commercial broadcast market like they had in the past since much of that is solid state today. There are fewer and fewer applications that actually require tubes now and the ones "hobbyists" send in for rebuild, are often not rebuildable due to arc pits in the anodes.
In order for Eimac to stay in business, the cost of this 800 watt tube has reached what a 3CX3000A7, 4,000 watt tube was 20 years ago. They are significantly more expensive than their Chinese competition and also built to last much longer. The only manufacturer that I've ever seen personally beat an Eimac tube, was Amperex and only with their glass tubes like the 3-500Z / 8802. Eimac stopped making all glass tubes soon after and neither does Amperex today.
Once Eimac is gone, you will no longer have the option to pay more for a tube that is built to last. They take punishment like no other and when run properly, last forever in our applications. I still have a set of four 4-400A, Eimac tubes in a homebrew piece of equipment built in 1963. They can easily be driven to run at full power with their plates glowing orange, to keep them conditioned.
This Alpha 87A is a masterpiece that retains good value when STOCK, clean and making full output. Once you start making any modification, including ones that alter the software to bypass the 11 meter lockout function, you will not only decrease its value, but you will also reduce the pool of knowledgeable buyers willing to pay for it.
If you have any intention of using it on the other HF bands one day, put this amp in a safe spot and save it for that day. You'll love its ease of operation and auto tune with band switching. Modifying it for 11 is risky business because even if you get the microprocessor to allow it, that doesn't mean the amplifier is going to like it.
How efficient is it going to run on 11? Does the plate choke have a resonance point anywhere within the 11 meter band? How will the input circuit need to be modified to match 11 meters and will that require losing a match on 10 or 12 meters? Will the tank coil need to be retapped? Will any of the band switching components or inductor be stressed on AM if someone runs the carrier up a bit too high? Is the grid current higher on 11 meters, than any other band when the mod is complete?
To me, it's kind of like having a luxury cruising machine and taking it to your local garage to have them modify it for a weekend at the drag strip. To do that job effectively, it may require more work than first thought and not be the easiest to reverse if desired in the future. It also increases the chances of pushing it beyond its design capabilities and failing. Keep this for HF and get something simpler (no microprocessor) for mono band use on 11.