xausa, bit strange to see an American asking us about shooting gear these days. I look longingly at US sites and wish like hell that there was some sort of free trade agreement between us. For a while post Howard there were plenty of parts, as many people broke firearms up, handed in recievers, and sold the rest of as spares. Unfortunately continued presure on shooters and dealers has seen a decline in the number of bits available. I have just fitted an M17 (US I think) sight to a No. 4 for a mate here,and manufactred a fixed site from plate steel for another mate, both based on cost. A No. 4 sight from a gunshop here was going for around $50 Aus,Plus screws etc. Bit high for a knockaround gun for the back of the ute (pickup truck). We still see them at gun shows, but not as often, and various shops have them sometimes.

Below are two that are worth a try. The first has no website (as far as I know), but is/was associated with Ian Skenerton (writer of all things SMLE)

Lee Spares, P.O. Box 770, Kingaroy 4610, Australia.
Fax: 07 4162 5785, international: + 61 7 4162 5785, tel. 07 4162 5366.

The second is a dealer who specialises in ex military, and in particular re-enactement gear related to the Australian Light Horse. He has a web site.

http://www.lawranceordnance.com/

Did you try Numrich, although I have found myself drooling less over their offerings lately, seems like you yanks are seing the same problems we have.