download the baggage rules for each airline you're flying. make sure you understand the specifics of how fees are charged for "oversize baggage" and whether they have a separate category of "sporting goods" with special rules.
check the size limitations. prolly not a problem for long-haul flights, but smaller planes going to smaller airports have smaller cargo doors. measure and weigh your packed box (with padding and tent and other stuff inside) to confirm you're within regulations.
print off the baggage/sporting webpages, upload a copy to your phone. write an email to the airline customer disservice center for confirmation, print that off, too. many reports of check-in clerks not understanding the rules.
you have connecting flights? check that both airlines (if more than one) have similar rules. two legs with one carrier will probably be charged two oversize/sporting goods fees.