MX-13 CRANKCASE BREATHER REPLCEMENT

[13petehoneytruck]

i am looking to replace the crankcase breather on my paccar 455 on my 13 peterbilt 587 because the truck has just turned over 500k and i know this part not being replaced can cause serious problems. the cost of the part was a shock as i was quoted $1,040 from a peterbilt dealership but i found the part at peterbilttruckparts.com for $895.76 and at bigrigworld.com for $773.57. i need to know if the part can be purchased for a less expensive price anywhere on the web and if the check valve and breather tube need to be replaced new at the same time. also can anyone tell me what is a good format to look up any part number for this truck. if anyone has changed this part themselves i would appreciate any advice to accomplish this without any set backs. appreicate any and all advise.