Design/Illustration for mobile app avatars

We have a social media mobile app with a built in avatar creation tool. We need a selection of adornments designed to our specifications to use within our app when building your avatar. We'll provide an initial layered Photoshop PSD file (CS4) with the base image in and we'll provide a list of adornments that we need designs for and the dimensions and specs for each one. For instance, we'll need a range of hats, shoes, glasses, shirts etc. They must all be provided ideally as illustrator files but definitely as transparent PNG files in 2 different resolutions (for standard iPhone and retina iPhone screens). For the scope of this project we'll be looking for quotes to design/illustrate 50 different adornments with each one provided in 2 resolution sizes. We'll assist with ideas for what they should all be but you'll do the artwork. If this goes well we'll have ongoing work for additional design. We'd like this to be turned around quite quickly so will be looking to accept a quote ASAP.