Mazda 3 Lease Special Through Credit Union?

Cross posting this from r/askcarsales because I didn't get much of a response:

Hi all, my credit union is running a special where we get $1 more than invoice, and as a result I headed into my local Mazda to get a lease quote for a Mazda 3 Sport sedan. I ended up getting $228 a month for 10,000 miles on a 36 month lease with $500 down that includes EVERYTHING but plates.

Is this a good deal? I don't think I'm able to haggle as a result of the credit union deal, does this seem like a reasonably good deal? Can I manage to get him lower by chance? Should I skip out on the deal and just try and haggle lower? This is my first lease so I want to make sure I'm not getting screwed out of a good purchase. Thanks so much!! I'm on Long Island if that makes a difference :)

Edit: My dad said to offer to sign right then and there if he removes the $500 down payment and sticks with the $228 a month. I'm not sure this is realistic, but is it worth a shot?