I did not like the sparQ-- the controls were too easy to turn on and the button panel stick out and obscures your L eye vision if you are R eye shooter (for both eyes open shooting), and the threads on the covers were so fine, that the covers are hard to get on/off.
The Bushnell TR25 is my choice for a cheap optic, with better controls (single turret rather than buttons), sits low without need for a riser.
Anything else like an AR style RDS (Eotech Aimpoint) will sit too high if you use the original stock, you'll have to see if you can get a good cheek weld.