Help in choosing zoom eyepiece for old spotter (1 Viewer)

Hello - I have what I think is a rebranded Opticron HR 60 armored spotting scope, model AA64-60SR. My scope is Japanese-made and was sold in the early 80's by Tasco as their World Class model 25T. I've enjoyed using the scope with its fixed 25X eyepiece, and I'd like to have a quality zoom for it.

The problem is that I'm out of my depth, never having anything but the one scope / eyepiece. That being said, I've found two zoom eyepieces that I think will work. Both are roughly the same price. Can I ask you all to weigh in on which of these two you'd buy in my position?

The first eyepiece is a Tasco branded model 10-1545X. The second eyepiece is an Opticron HR2 model 40933. I've attached pics of each.

If you all would be so kind as to advise me, I'd really appreciate the help!

Hi,
I have the 40933 HR2 ZOOM eyepiece.
I bought it at a low price as an oddment, when I was buying something else. It came with a six month shop guarantee.
I have not used it except maybe once to see if it fitted something.
It could be 7mm to 21mm focal length, but I am not sure.

(Non stop fireworks outside, noisy, but sometimes nice to watch.)

The eyepiece is multicoated, mainly green, some amber, some blue, possibly single coats.
Japan.
This eyepiece may have been old stock unsold as it looks new.
Twist up eyecup, 11mm travel.
Front and back caps.
Back cap says GS or MM2 scopes need 40934 adapter.
The eyepiece seems well made.

HR66 and HR80 don't need adapters.

Box says 20-60x HR66.
Also HR80, ES80, ES100, GS665, GS815, GS52, MM2, IS50, IS60, IS70. Magnifications are given with each.

The apparent field is wide at high power, rather smaller at lower power.
Some of these scopes need an Opticron adapter, which they probably still have?

The box does not mention HR60.
If there is an HR60 then the magnification could be around 18-54x?

With the IS60 the magnification is 16-48x, but needs adapter 40928S.

Box barcode numbers say 5 036422 409331 HR2 eyepiece.

I don't have the Tasco eyepiece so cannot compare.
The Tasco zoom could be 8mm to 24mm focal length?

But any eyepiece that fits your scope could be useful.

Regards,
B.

P.S.
I would buy the eyepiece in the better condition, from the most professional of the two sellers.

Binastro - thank you for the very detailed description of the Opticron 40933! That was very helpful.

Even though the Opticron is a demo eyepiece, its the one I'm leaning towards. The Opticron's seller will allow me to return it for a full refund if it doesn't work with my Tasco 25T, provided I pay for the return shipping. The Tasco is a brand new in box eyepiece, but it's seller wants certified funds with a no return / no refund policy.