I buy all my leads for everything from the Pound Shop. Never had any problems.
Angle finder 1 http://www.vansantent.com/angle_finders.htmYou can buy these at an good stationers art shop.
It's worth buying a cheap one from a medical shop. About a fiver or less.
The sequence you need is: go to shop, buy new one, come home and fit!
Or something a joinery shop could run up easy enough.
Also try dope thinners from a model shop. Or cellulose thinners from builders merchants etc.
Or a fabric / curtain shop where they sell it - to spray on curtain track rails !
no more nails, or any of it's cheaper counterparts, your local plastics shop is correct
Because you'll see it's a very odd size, and not stocked by a "real" shop.
Between my house and a trip to the shop a quarter of a mile away.