My favorite is the Leapers airgun rated TS(True Strength) 6-24x50AO. But that wont fit on all guns because its long. Same with the Leapers 4-16x50AO. I've had really good luck with the BSA 3-12x44AO airgun scopes, but they are not mildot reticles, but they fit on a good portion of my springers...not as long as the Leapers.
FWIW I have found the Hawke customer service and support to be among the best in any industry. You go right to a human, who has a clue, and wants to help.