Walther PPX, M&P, Beretta PX4 C format/ambi line....
If you can wait you can buy a NIB(new in box) Walther PPX. It's a hammer fired high-cap polymer frame DA only pistol in 9x19mm or .40S&W.
It's full of ambi features & the projected MSRP is about $500.00. Note: prices may shoot up with the big upswing in sales/interest.
Other good, high quality brands include the Beretta PX4 Storm in C(constant action) or the ambi-feature Compact. The compact has a slide mounted ambi safety, ambi slide release, ambi(converted) mag release. I owned a great PX4 C 9mm in 2009.
The HK-P30 or P2000 series could meet your needs. They have ambi controls & the LEM(law enforcement modification) is popular with LE agencies(ICE, CBP, US Border Patrol).
I lean towards the .357sig for defense/concealed use. It feeds good & is powerful. The FAMS(Air Marshals) & US Secret Service use it with + results.
Every 2nd matters.