How can I make Products with a certain SKU unable to buy?

Hello , I added this code to my product-template, how can I make products with this sku unable to order, I dont want it to be like “not in Stock” outgreyed and listed at the end of the productlist, just not orderable.

Thank you very much

{% if current_variant.sku == 'SKU1'%}   Nicht lagernd
 {%endif%}

waffen-paar.at

Example: https://waffen-paar.at/products/kopie-von-alfa-carbine-stainless-9mm-para-oder-357-mag-kat-c-frei-ab-18