Tonearm for the Michell Gyro SE MKII

My Gyro SE came with the usual arm: RB300. I'd like to try other arms but I can't quite see how to deal with the issue of armboard - presently I'm limited to those that use an armboard with a 1.125" thru-hole (I think that is the hole diameter of my armboard).
I need some ideas. To those of you who are using non-Rega style tonearms with your Gyro SEs - what are you using? how are you doing it?
I have a Orbe SE + SME V + Shelter 901. I had originally had my eye set on the Gyro SE about 4 years ago, but ended up splurged and got the Orbe and the SME V instead.

Expressimo or Origin Live fully modded RB250 and RB300 are both excellent and popular choices for the Gyro SE. That was the route I had originally planned on taking. If you have some extra cash, I would choose either an SME IV.Vi or an SME V. Gyro is a popular choice with my local audiophile group. I have heard several tables set up with modded RB250/RB300 and SME IV.Vi. The SME is a better choice hands down, several Gyro owners here have upgrade to the IV.Vi from modded Rega arms. But the modded Rega arms wins in the price/performance ratio category. Michell used the SME arms in developing all their tables, so there's synergy there. I have not heard it myself, but I would presume that Michell's own techno arm should be a good match as well.

Just so you know, you can order a different armboard from Michell. When I ordered my Orbe, I specifically asked for an SME armboard.

I have the SME V on a Gyro SE and I quite enjoy the sound. I have used it with a Koetsu Black and a Clear Audio Aurum Beta S. I am thinking perhaps a Shelter 501 or a Grado Reference, but the SME V is definitely sticking around. I have the SME specific armboard as well.
Besides the arm cut-out, the arm boards are designed to weigh the same with each arm mounted to keep the suspension balanced.
Thank you for your ideas. They are just the encouragements I need. I'll look especially at the SME arms.
To Frank (Gundam91)or to others if you know: Do any of your friends have two arms on their Gyro SEs? It appears to me that the second mouse ear could be used for a second arm if I moved the DC motor out of it.
Yes, you can. I have seen it done, and have contemplated that idea myself, so I can add an arm with a mono cartridge. All you need to do is to have holes drilled in them to accept armboard plates, and you can move the motor to another location, just make sure it's the same distance from the center of the platter.

You can e-mail Michell Engineering to see if they would drill the holes for you, or you can find some local machine shop to do it, I guess.