So I'm wanting to install my UBR onto my rifle but I need to buy a sling plate for the rifle since I'll be using most likely a ms4 sling, and everything is going towards the QD socket system so I'd rather not go with an ASAP plate like I have on my SBR lower. Is there one that will have a QD socket in the center, since I'm a lefty but I try to train left and right handed to keep the skills up. So far I've found a Troy sling plate that has left and right QD cup but no center socket, for $22 on ebay. Wondering if there's any other better options out there that won't break the bank.

The IWC adapters for the UBR are excellent - they are about your only option for a UBR.

do you have a link for this ?

QD: http://www.impactweaponscomponents.com/product/csap-qd-mount-n-slot-for-magpul-ubrtm/
Snap hook/MASH: http://www.impactweaponscomponents.com/product/c-s-a-p-mount-n-slot/