You should use your theme’s search page, instead of WPSOLR’s Ajax search template in screen 2.1 option “Search template”. It will be much better integrated with your theme (activate our WooCommerce extension also. We have WooCommerce tutorials too).
Also, you can add Ajax and advanced facets layouts to your theme too (price slider, ranges, select2, color picker ….).
With the WooCommerce extension installed, you can index and use attributes as facets, like the _price (with a nice slider facet layout).
Keep in mind you’ll need to reindex all your products.