I’m on my parents plan and have a iPhone that’s starting to not work but didn’t receive my current phone through cricket, is there and good deals to buy a new phone through that plan or am I better off just buying on a different site?

Long time Cricket user with $100 family plan. Two phones on plan are iPhones 13 Pros that were purchased from apple and brought to the network. Two of the phones were bought from cricket iPhone SE. the SEs are pretty much shot with no battery life. I see cricket is offering iPhone 11 for new customers for $99. But for existing customers to upgrade its $499. I understand they want new subs but they should reward longevity as well. I’d be willing to switch to new carrier even if it’s a little more expensive in order to get the phone upgrades. Any options out there?