OscAddons.com offers all kind of support for OsCommerce online stores.
You will find add-ons which add functionality and features to your store and which are compatible with 2.3.4 Responsive Bootstrap version.
A version of OsCommerce 2.3.4 responsive bootstrap, oriented to the Spanish market and with specific support for Spanish language.
At your disposal there are completely free add-ons which you can also find on the official OsCommerce website, and a selection of commercial Add-Ons with very affordable prices and exclusive on this WEB.
On the other hand you can count with installation and programming services at very competitive prices.