I cant be sure if the book is an old TSR book or not. On the cover was a man flying on a magic carpet. The plot goes a team of adventures consisting of a fire mage, barbarian, a male thief, female thief/werecat, a dwarf, and a very alcoholic priest go on an dungeon crawl to a nearby dungeon. In the course of the crawl the priest accidentally gets poisoned by the dwarf when the group was fighting a dragon or other large beast. After they kill the beast they are captured my a evil cult of orcs (I think), and taken to a magic metal statue to be sacrificed. The statue is actually the last human king, and helps them get free and kill the cult they get the treasure and the statue and take it back to the city. All the mages in the city are interested in owning the statue for the metal and proceed to fight over the statue and destroy the house where part of the party was staying. I can only hope someone out there can remember the name of the book or an authors name.
You're thinking of the swords-and-sorcery parody Another Day, Another Dungeon by Greg Costikyan (the game designer). It wasn't ever a TSR publication to my knowledge but it plays with role-playing game tropes. Recently graduated fire mage Timaeus d'Asperge gathers an adventuring party [two thieves (one a werecat), a Conan-esque barbarian, a dwarf, and a priest] to explore the local caverns rather than join the army. The party does, in fact, fight a dragon and recover a hoard of treasure before the priest gets poisoned. The party discovers a statue made of the magical metal athenor containing the spirit of the last human king under an orcish altar, which they have to defend against wizards in the Battle of Five Corners.
There's also a sequel (One Quest, Hold the Dragons) but the series was never completed.