I agree, except with the word "slightly". It can be so significant that this increased cost/friction is the very mechanism of the sanctions' effectiveness. Is it possible to police the Russian oil shadow fleet to extinction? Maybe, but even without doing so you can impose a decent haircut on their profits by issuing scary-sounding press releases and leaving it at that.

Increased costs might be a factor in a competing commercial market, but for military purposes, you buy the components no matter the price or search for an alternative (China is now making lot of components - for example, resistors, transistors, logic chips - I have several 74HC chips of Chinese origin, and they are very cheap). Also, there are thousands ships and no legal basis for "policing" them in open sea.