Appreciate the responses and information so far, guys. Here are just some examples I've found on a common site. Are these blatantly obvious fakes? My worry is someone making a game "complete" by purchasing pieces that are repro and making a more money from the sale. But, I could always avoid auctions as already mentioned!
https://www.etsy.com/listing/609569601/avp-breakout-2000-replacement-box?ref=related-1
https://www.etsy.com/listing/581704536/nba-jam-tournament-edition-for-atari?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=atari+jaguar&ref=sr_gallery-1-15&organic_search_click=1
https://www.etsy.com/listing/664176912/wolfenstein-3d-jaguar-replacement-box?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=atari+jaguar&ref=sr_gallery-1-19&organic_search_click=1&cas=1