You can use regular expressions with redirects, so something like this - although I'm sure the syntax is not exactly correct, hopefully you get the idea:
Redirect 301 /somedir[0-9]*/694-(.*) http://www.website.com/blabla/$2
[0-9]* says to match any number between 0 and 9, zero or more times
(.*) matches any character, zero or more times
$2 will copy the contents matched by (.*) and preserve them
These links may be of some help:
http://www.gnc-web-creations.com/301-redirect.htm
http://httpd.apache.org/docs/2.0/misc/rewriteguide.html