The Left Dash X is another lower spin option. Buying a couple of sleeves is a low cost option.

Both may lower the spin number. Enough? No idea. Your fitter saw you and the numbers.

Titleist allows you the opportunity to compare any two balls in the inventory if you choose to do that. Click on BALLs above. If you want to compare the AVX's performance to any of the other premium balls, then click on the AVX ball box picture and go to the bottom of the ad and go to "go to my ball". The AVX ball should show on the left. On the right side you can scroll down on any ball you want to compare it to in the titleist inventory. That is kinda helpful. Then get a sleeve, as Don suggested, and do an on course comparison. If you went to a Titleist fitter, am pretty sure he put you in the right ball. Good luck.

AVX is not a bad low spin option but I would lean more in Don's direction. I used to play AVX. When I got fit out in Carlsbad by a Titleist fitter he asked me what ball I played and I said AVX. He asked my why. I said because I'm a very high spin player which was even verified by my numbers. He recommended I play ProV1. When I asked him why he said there is a reason you don't see anyone on tour playing them. Even though AVX was marketed at the lowest spinning tour ball, it's not a tour ball.

An uneducated opinion, just to throw it out there, is AVX I would look towards for ball flight trajectory more than spin capabilities. It is a low flight more than anything. As Don O suggested, ProV1x Left Dash gives you a higher flighted firm ball with low spin also. Just up to what feels and looks right for you on the course.
Go get em!