Which bird box camera

Hi Kevin,
90% my boxes are from Gardenature
gardenature.co.uk/shop/watching-wildlife/bird-boxes-with-cameras
These are more high end boxes and cost over £100 a kit
You can check all my videos out here on youtube
www.youtube.com/channel/UCO9rS6eR83eCQswvJNgyHwA

If you are looking more for a cheap set you can go for the likes of Handykam or BirdBoxView

You can check Handykam kits out here - www.handykam.com/product-category/wildlife-cameras/bird-box-camera-systems/
wired version starting at just £40

Birdboxview is a company I have worked with on twitter who do wired / pc version they have set me a few of their boxes to test and review for free in the past / do giveaways with. 
While quality isn't amazing for how cheap the products are its good enough for the price, Although their wired camera sets are alot better than the pc ones.
You can check their products out here - birdboxview.co.uk/products

Hope this helps, It all depends on your budget, The cheaper products wont show great colour however you can pair it with an led light for just £9.99 here - www.green-feathers.co.uk/products/daytime-led-lamp-for-bird-boxes and it will improve the colour greatly for you.