Keep in mind this worked in v3.1.1 so I'd recommend commenting out lines in the tpl's instead of removing them
To get "sold out" on 0 availability products:
skin1.conf
Code:
UnlimitedProducts = "N"
And in customer/main/product.tpl:
comment out this piece to remove the quantity of stock available from being shown
Code:
{if #UnlimitedProducts# ne "Y" and $product.distribution eq ""}
<tr><td width=30%>{$lng.lbl_quantity}</td><td nowrap>{if $product.avail gt 0}{$product.avail}{else}{$lng.txt_no}{/if} {$lng.txt_items_available}</td></tr>
{/if}
Hope it works for you!