Perceptron Mk1 and Lyria 3 Pro Preview are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Perceptron Mk1, from perceptron, has a 32,768-token context window and is priced at $0.15/M tokens input, $1.50/M tokens output on OpenRouter.
Lyria 3 Pro Preview, from Google, has a 1,048,576-token context window and is priced at $0.08/song on OpenRouter.