how to get rune scim? and other questions

for question 1 is it wouldn't be worth grinding and i'm not sure for the drop just buy a longsword from the champion guild you can enter at any level

for question 2 you can buy a dragon scim from a guy at a port forgot the name but ask somebody more then likely the same as you went there with

for question 3 it's an uncommon drop

for question 4 don't alch just alch items you don't need metal mainly and alch dragon sq shield pieces you can't get it for money do green dragons crafting and prayer xp is needed badly you should be able to safespot them to the trees on west the two close together just sell them to a high level player like pwnbychris or ajim