Looking to Develop a web shop

Description

Hi - I am looking to develop my current opencart web shop or start from scratch & create a whole new web shop. Functionality needs to be similar to this competitor of mine https://www.theuniformroom.co.uk/p_anthem-midweight-t-shirt_8205.
I would need the tabs to include the cost of various print / embroidery options to be included in the price at checkout
The current open cart is https://embroidered-workwear-shop.dynamicembroidery.co.uk/ - but it's not working correctly at the moment.
I would need 300 ish products loading - they are all clothing/garments so all have size / colour options.
I can get data files from my main supplier, but that is 1000's of products, and you would need to check the format is suitable (they provide full data, shopify data, woocommerce data and an API) We would only need 300-500 products if we use that data - I can supply a spreadsheet on request - otherwise I can provide a spreadsheet to their website & the products & images would need to be loaded manually
Please only respond if you have the capability to deliver this project
Timescales - I can work with you, but I prefer to get it done right rather than done quickly!
If you know what modules need to be purchased - or have a rough idea of the additional cost of external modules, let me know that