Was looking at one on an auction site. What is a good price for one ? Can this rifle be scoped or can some kind of firesight be put on it.

Hard Luck....I don't know what they are worth down in the states...I do have a #3 in 45-70 and have been loading for it..as soon as my back gets better I'll be taking it to the range....
Scope-----Yes I have Ruger bases and rings
Firesite----the front site is your standard dovetail so it should be easy to find a fire-type site for that...Mine came (used) with Williams receiver site so I will be using that for the rear site after I have worked up some loads with the scope...
Loads----mine will be lite cast loads 340-360grs. up to 1500fps

In my neck of the woods, Ruger #3s in 45-70 run right at $500 and up, mostly up lately.
Paul B.

$500 to $600 here if it is an perfect condition.

My Ruger #3 in 375 Win did not have provisions for scope mounting nor did it have the 1/4 Rib.
I fitted, drilled and tapped Weaver bases and installed Burris Z-rings with the exentric plastic inserts to compensate for the minor mialignments of the bases.

No. 3's are drilled & tapped to use a pair of bases that Ruger used to furnish, so they can certainly be scoped. The No. 3 will tolerate loads that no-one can stand to shoot due to that buttplate which allows the recoil to remove your shoulder! It is best to put a regular buttstock with a good recoil pad on the No.3 in .45/70!

That one ZERMEL is showing is done right!