A search on Google for VHS tape conversion yielded many results...this one looks pretty reasonable -
http://www.hightechproductions.com/conversi.htm It's been awhile since I had to convert anything so I don't have any personal recommendations but there are tons of places.
It does not hurt/compromise your original PAL tape at all. But depending upon the quality of the conversion the new NTSC tape may be grainy, especially if the place isn't using studio quality reproduction equipment.
Leche
[This message has been edited by Leche (edited 10-10-2000).]