How to redirect specific links to https:// everything else to http:// using .htaccess?

Question

I am trying to use htaccess to automatically direct all requests to certain pages to https and everything else to http://

Here is the code I've got the code to force ssl working below

RewriteEngine on
RewriteBase /

RewriteCond %{SERVER_PORT} !^443$
RewriteRule ^va-homebuyers-guide https://domain.com/va-homebuyers-guide/ [R=301,L]

RewriteCond %{SERVER_PORT} !^443$
RewriteRule ^va-purchase-request https://domain.com/va-purchase-request/ [R=301,L]

RewriteCond %{SERVER_PORT} !^443$
RewriteRule ^va-streamline-refinance https://domain.com/va-streamline-refinance/ [R=301,L]

This is working as expected and redirects to the ssl versions of those pages. I then tried adding the following to redirect everything else to http:

RewriteCond %{SERVER_PORT} !^80
RewriteCond %{REQUEST_URI} !^va-homebuyers-guide$
RewriteCond %{REQUEST_URI} !^va-purchase-request$
RewriteCond %{REQUEST_URI} !^va-streamline-refinance$
RewriteRule ^(.*)$ http://domain.com/$1 [R,L]

This code results in a redirect loop when going to /va-purchase-request /va-homebuyers-guide and /va-streamline-refinance and does not redirect the other pages at all.

I'm totally stuck with this and any help would be massively appreciated!

Edit:

I also have this code in the .htaccess file added by wordpress... Could it be interfering with the other redirects?

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

Answer 1

Replace your .htaccess code with this:

Options +FollowSymLinks -MultiViews
# Turn mod_rewrite on
RewriteEngine On
RewriteBase /

RewriteCond %{HTTPS} off
RewriteRule ^va-(homebuyers-guide|purchase-request|streamline-refinance)(/.*|)$ https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L,NC]

RewriteCond %{HTTPS} on
RewriteRule (?!^va-(homebuyers-guide|purchase-request|streamline-refinance)(/.*|)$)^.*$ http://%{HTTP_HOST}%{REQUEST_URI} [R=301,L,NC]