Upvote:1
A scanned, color copy is what most people use to apply with. Normally the tourist agency does not mail you the original letter of invitation, they simply email you a scanned color copy, which is acceptable to apply with.
You could request the original to be mailed to you, but I have had a lot of problems with mail delivery to and from Russia, so I wouldn't get your hopes up of it arriving in time or arriving at all.
I have never received an original letter of invitation and I have been to Russia four times on 3 different Russian visas.