sealant as alternative to water based varnish

i want a clear water based varnish for some pine funiture. i have used one by homebase and it does the job just fine, but is quite expensive. is there any alternative i could use thats more economical ? like some kind of builders waterproof sealant?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.