Ox Alpha and Aion-3.0 are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Ox Alpha, from Stealth, has a 1,048,576-token context window and is free to use on OpenRouter.
Aion-3.0, from Aion Labs, has a 131,072-token context window and is priced at $3/M tokens input, $6/M tokens output on OpenRouter.