I got a Flexispot EC 3 standing desk with 55”w x 28”d curved front top (curved front tops are no longer offered) and added one of their monitor arms. Paid about $525 for the desk and $80 for the arm. I’ve used it for about 15 months and it is fabulous. If I did it again I get the newer EC-4 base (wasn’t available at the height of covid) and motor to be able to lower the desk another couple inches when sitting.
They have other less expensive options too.