Ike Stewart

The only citrus I would consider planting outside on the 7b / 8a line would be Arctic Frost (Satsuma hybrid), Orange Frost (Satsuma Hybrid) and Miho Satsuma (in that order, which is also worst to best tasting), even then expect to need active freeze protection when temperatures drop below about 18 degrees F.      Active freeze protection includes covering tree and using heat lamps /  incandescent Christmas lights  to maintain safe temperatures.    Kumquat trees may survive in your climate, but will likely fruit too late in the season (Feb / March) for you to get any fruit unless you actively freeze protect maintaining temperatures around the tree over 25F.      Miho is an early fruiting Satsuma, typically early October about 3 weeks ahead of Owari, I am not sure about the "frost" hybrids.

Meyers can generally survive temperatures down to the mid 20's though will suffer leaf loss, and perhaps some die back.  Though in the future I would suggest active freeze protection in your region, this includes covering and heat lamps. Given its current state give it time to leaf back out, citrus can be very slow to leaf out after a freeze, one of my mature citrus trees lost its cover in the 15 degree freeze here a couple of years ago and did not leaf back out until August, it also had over 50% die back.

Try Leggcreek nursery in east Texas  they are doing their end of season sale right now last day to order for the year is tomorrow

I received a promo coupon email from them a day or so ago 15% off on orders of $50 or more code 15OFFNOW

I have bought from them 3 out of the last 4 years, overall I rate them a good B+ though be aware their native fruit trees are small and they made mistakes on 2 of my orders, though to their credit they corrected the mistakes (my second order was missing half the order in the  box)  

They claim to offer regionally appropriate fruit trees, and they are located in mid 8B in east Texas a bit south of I-20