What year is it? These are great boats! A little on the heavy side but very solid. My buddy has one and I actually prefer driving his over my Rogers. The Hallett seems to be a little roomier too. Hallett is still in business and they're not making anything remotely close to what you have. I heard they they are being built in Australia now? I believe that the Sprint was designed by a man with the last name Barron. Either he worked with or for Hallett. I'm not sure.
Its a 1980, have had and driven other 19' halletts (bubble deck) and it drove very nice and predictable. Had a blown bbf in it, very stable over the century mark. I think that Hallett was the name of the designer and Nick Barron was the man whose factory laid them up (or visa-versa). Kind of like Fred Wikkens and the Aqua craft deal.
The sprint has some of the biggest stringers i have ever seen in a boat and has no stress cracks in it, guess thats why they wiegh so much!