If it's drilled like this then you have a bunch of choices - Williams, Lyman or older Redfield. The older all steel Redfields or steel Lymans are preferable IMO for a nice rifle like that but a aluminum Williams FP or Foolproof would work just as well. That tang safety unfortunately negates the opportunity for any number of excellent tang sights.

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Gunnery, gunnery, gunnery.
Hit the target, all else is twaddle!