any suggestions on the loudest air horn for the nitro?

i'm looking to buy some or one air horn with or without a compressor that is not too expensive, preferably less than $100 total, louder than a train horn and can be located in the engine compartment or on the front bumper area without looking like a piece of junk work.

have looked on many websites and this is one that i have found so far. it is on this site....www.buyautotruckaccessories.com and they are the "wolo extreme air horn, blue". there is a play sound button to here them and the complete kit costs $26.95 without the shipping. let me know your input and if you have found anything better. thanks again!

mcnabb in louisiana.............