Ah, but what is the current rating of the original? It's not in the service info.
The only thing I've ever found is this which rates them in wattage - not current. I assume 5.6 ohms at 5.6 watts translates to 1A. I've measured the B+ current in a few sets and it's slightly over 1A.
Watch this for suggestions on replacing them:
https://youtu.be/hYDJZvHPM1A
