That oil spatter could be a number of things. Those early slopers had no oil seals on the guides - not even on the exhaust guides, but they rarely spit oil.
It could also just be a motor full of oil, poor ring seal on the oil rings, oil in the pipes or just a motor that has not been run for a long time.
If it runs OK, I'd be tempted to run it for a while and see if it improves (storage oiling) or stay as bad (something worn).
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