replacement watts washing machine shut-off doesn't fit

I am replacing a Watts single lever laundry shut-off valve that leaks at the lever. The replacement unit is Watts SKU# 0006644.

The problem is the I want to use the sweated on elbows from the old one and the recess where they fit into the unit with an O-ring are different on the new one so it does not seal tight.

I did install it using a fiber washer and the o-ring and tightened the h_ll out of it. I am not sire that will hold up...

Does anyone have another solution for using the replacement shut-off with the old elbows?

Thanks! Jim