1. Strathearn was 1964 to 1980. It was the renamed version of the Vasart Ltd company.
2. Pirelli Glass marketed Vasart paperweights, as well as their own non-paperweight items. But they had nothiing to do with the calendars or the tyres. The label dates the weight as 1956 to 1964, although it is not known for sure whether the Pirelli connection stopped before 1964.
3. The one-inch (or so) items might be Vasart or Strathearn miniature weights, which were production items, not so-called "end of day" work. But without details or preferably a photo, it's obviously not possible to say whether they really are Vasart or Strathearn.
The prices for Vasart / Strathearn weights vary according to the size, condition and type - they could be anywhere from Â£5 to Â£200 (!) although Â£30 to Â£80 is a usual amount for regular non-faceted millefiori items. It's a good idea to check eBay or main paperweight dealer sites for general prices.
Good luck with the auction. If you get them, please post a photo or two.