If your using Bilstein HD's the bump stop is internal and the boot is included. If your new strut's don't include boots I would get new ones. FCP also sells a boot with the bump stop included.

IMHO the orginal mounts are superior to the ones sold today even the SKF's and I will sometimes reuse them if still in good condition. You can check for any rubber separation while still installed. If you see separation then replace. As an example on a 1990 240 with 280K one mount had separation and one had a rough bearing which could only be determined when removed. On a 1990 240 with 160K both mounts where good and I re-used them.