Hi,
I'm so sorry to hear about the condition of your little guy. I know how stressful it can be to have a sick chameleon. Blood in the stool is most likely due to parasites in his digestive tract, probably coccidia. A lot of chameleons are carriers of coccidia and can live completly healthy long lived lifes. Some people even think coccidia is naturally found in the gut of all chameleons and is just kept in check by the chameleons immune system. Unfortunatly stress can cause an outbreak of coccidia that the chameleon cannot come back from without treatment. If your guy does have coccidia he probably had it in his system and the stress of shipping and a new environment caused an outbreak and resulted in where he is now.
First things first,
1.) Up his ambient temps into the 80's 24/7. Chameleons being cold blooded cannot manually raise their body temperatures to fight off diseases and such like warmblooded creatures can(fever). So in order for him to have the best chance of staying alive you need to keep his temps elevated so his immune system can try to do it's thing. This is jsut to keep him in the best condition possible until you can get him to the vet.
2.)Get him to the vet!
https://www.chameleonforums.com/veterinarian-resources-67/
https://www.chameleonforums.com/area-area-country-vet-list-32880/
You can use those threads to help find a good cahm vet in you area. The vet will run a fecal exam(save all his poops in the fridge, never throw them away cause the vet is gonna need a fresh sample) and try to figure out was is causeing the bleeding in his digestive tract. Bring all the poop you can cause some vets need a certain amount in order to run a fecal but know which one is the freshest in case he only needs a little bit.
3.) If it is coccidia(most blood in the poop is caused by this) try and get a drug called ponazuril NOT ALBON. Call the vet ahead of time to see if they use this drug for coccidia cause it's kinda new and some vets do't use it yet. The reason you want this ponazuril and not albon is a.) albon is very hard on the organs of your chameleon b.) ponazuril actually kills the coccidia where albon just supresses it enough for your chameleons immune system to fight it off. You will also have to continually clean his cage several times during the treament because coccidia is transmitted through feces and every time your chameleon poops he basically drops coccidia eggs that get spread around by him, prey items, and such. These eggs(oocysts) last a LONG time and if your chameleon reingests one after he is treated he may get infected again. You should look up on the forum how to do this cleaning. Basically your gonna wanna boil or use highly concentrated hydrogen peroxide(the stuff for bleaching hair) to kill the eggs every time you clean. I know this is a pain but it's what you gotta do.
4.) Lastly keep him quarantined from your other chams. Those eggs I talked about can be spread to your other chams very easily if you touch him, inside his cage, or anything that has been inside his cage and then go deal with your other chams. DO NOT put uneaten feeders from his cage back in your cricket bin or to another cham. The best thing to do would be to buy some latex disposable gloves for when your dealing with him as washing your hands is not guarenteed to get everything off.
Thats all I can think of for now. Keep us updated and let us know how he does! I'm pulling for the little guy!
Good luck!
-Alex