I think it's hard to capture in a few numbers - it's not exactly analogous, for instance in Martha Gellhorn's The Face of War, specifically her reports from Western European theater of WW2, she could never forget that part of the stated purpose by Nazi officals for those concentration camps and other captured peoples made to work for Nazi regime in other areas was to extract maximal economic value from them while working them to death and the German people as a whole felt essentially zero impact on their day to day life and benefited from the crops and material looted from captured territories or created by those captured by the Nazis, not to mention all the valuables looted from the people sent to concentration camps in forms of their business capital/jewelry/extracted gold teeth/other personal valuables. In one sense these current day agricultural/trade workers/labor system are subsidizing a lower price of some agricultural/trade products at least in the market we had. If we had a perfect market, the labor cost should go up in their absence to attract domestic workers in hand with end product cost though this has not happened in several prior crackdowns on undocumented immigrant labor in the USA. In addition to direct citizen monetary costs we might count a.) the spending on ICE b.) the discretionary funding by executive branch to farmers/ranchers to replace lost income as happened in aftermath of Trump's first term tariff regime.