Hi Roos, welcome.
Go to this forum:
https://goscf.com/f/12Start a New Topic and title it Avatar Request or something similar.
To add pics there is a tutorial on the left menu bar called Uploading Photos.
However, remember to use the link Reply To Topic on top right of a topic page to reply, not the bottom Quick Reply area. The top link will open the Message editor which, at the bottom of the space, has a little green camera icon.
Your photos / scans must be below 100kb in file size to load to the forum. No spaces (use dashes or underscore characters to separate words), no special characters in the file name.
There are online photo resizers at
http://webresizer.com/resizer/ OR
http://www.picresize.com/OR you can load your photos to a picture hosting site like Photobucket or Flickr (see tutorials made on how to use these (search on Stamp Community)). The only issue with using these is that the photo scan is not on this site and could possibly get erased / moved and then we have lost it here.
Then, once a photo / link is put in your post, wait some days or so for the Admin folks to get to it and make it your avatar.