I did not try to figure out if Amazon in Germany will ship to Columbia or not, I will let you research that. I am not sure what the difference between Marathon Plus and Marathon Plus Tour is but they have the Tour version in Germany.
https://www.amazon.de/-/en/SCHWALBE-...dp/B004MMVT1Q/
When I ordered from Amazon in Germany for shipment to USA, I used a credit card that did not charge a currency conversion fee, I told Amazon that my card used Euros to avoid a currency conversion fee.
Or check what else they might have.
https://www.amazon.de/s?k=schwalbe+marathon+plus+50-559
SJS in UK has them, they ship to lots of places. Is this what you wanted? But since Covid, SJS shipping costs have been a bit high, check that before you get too detailed in your search. SJS has sold a lot of 26 inch touring bikes (I have two of them), so they have a large customer base that looks for that size.
https://www.sjscycles.co.uk/tyres-la...00-inch-50559/
Last time I ordered from SJS was 2017, their shipping fees at that time were quite reasonable, but that was before Brexit.