The picture on Unicomp's site is kinda low but from the evidence I've gathered I would say they are not Unicomp's APL keys but rather IBM/Lexmark transition era. I did get one so I can share my findings. One hallmark is the font itself! The font Unicomp used on their APL keys is different than what IBM used. Unicomp's are a light orange color possibly with fading in some places. This was before they switched over to the current offering of the blue APL keys.
Exhibit #1 - The OG of OG IBM APL keys
Exhibit #2 - IBM 1389194
This keyboard was not intended for PC use, but rather with a 3192 terminal for mainframe computers (3270 coax interface). We also see these APL keys on some F122's.
Exhibit #3 - IBM APL keys sold separately for the Model M (NOS from the box
). Likely Late 80's/early 90's vintage.
Exhibit #4 - Older vintage Model F/M APL Vs Unicomp Orange APL
Exhibit #5 - Present Day
Finally putting it all together...