Honestly I'd rather have the ability to produce Ogre's than come up with a new suit.
There is the Reactive Armor Rogue Bear. Sure 4 shots isn't 13, but who uses 13 rounds and it has better armor and generates a jumping to-hit modifier.
I would like a golem if was good.
Try Golems in the city, especially with alternate Bear Hunter rules.
Alternatively try Golem Support.
Upgraded Rogue Bear with AP Gauss, a Quad Assault Suit, and a fast boy to keep up with the Horses Quad whose name I forget at this moment.
SRMs tend to be equal to APGRs if you have enough ammo. Enough depends upon armor.
A quad is not going to happen.
You can only keep up with a Buraq by going quad or a very very light VTOL. Whether you really need to keep up with a BA that can only crack 70kmh is a different question. Like doesn't have to fight like.