bad oil cooler

[ktbtrucking]

have cm870 and noticed drop if my oil pan for around 1gal on short 140miles run. Added a galon of oil and made another 60miles. Discovered my oil went into coolant reservoir and started to overflow through overflow cap. Removed both hoses from reservoir ,one is from radiator ,one from coolant housing and it drips still red coolant. Have reservoir fool of oil mash. Made a 30miles trip to the dealer . Have a 500miles home and empty trailer. Should I change oil cooler at the dealer or try to get it home and fix it there? Any advices? I completely understand that all situations are different though with same issue made 1000miles with 45k but as a company driver. :)

truck runs, no overheating but noticed oil pressure up around 2psi