I recommend the Rockware sliders. They are frame mounted rather than sill mounted like every other slider out there. In my opinion the design is superior if you think you might have any amount of the vehicles weight on them at any point. The sill mounted type will bend the sill and the sliders will rotate up towards your doors. You can bend them back, but you shouldn’t have to.
I think most sliders run $400-$500. Rockware will cost more like $700 if I remember correctly. They can add tube steps if you want. Just give them a call. I think they’re still in business based off a Facebook page.