Force SSL on one page only

Server Config
1

This code …


RewriteCond %{SERVER_PORT} 80
# RewriteRule ^(.*)$ https://www.example.org/$1 [R,L]

in .htaccess works fine if I’m making all my pages become SSL.

But I want only one page to be forced to SSL. Say, this page…
http://www.example.com/payments/pay/

Rest is normal non-ssl. How?