I would like to know wether and how I could implement a lottery. We will have respondents complete a series of tasks and get a score. We will randomly match their scores to scores from participants from a pilot, based on the random match, they will be declared the winner if their score is higher than the score of the participant from the pilot.
We want to give the winner 10 tickets for a lottery to win a prize. We would like for these tickets to be numbered (because after data collection is done we will then randomly select 1 ticket and contact the owner of the ticket to give them a prize). So, if we have 2000 respondents in the survey that will be randomly matched to scores from participants in a pilot, that means that there could be quite a lot of winners (depending on how good their are). So quite a lot of numbered lottery tickets. We were thinking perhaps creating a csv with numbers from 1 to 20.000 (just to be safe, it probably won't be the case that all 2000 respondents score higher than those 100 people in the pilot but this is an upper bound). Then we would like to figure out a way in qualtrics that if the respondent wins lists 10 of those numbers as tickets for the lottery given to this respondent. It is very important that these numbers are assigned WITHOUT replacement, because no two respondents should have the same lottery ticket. Once a ticket is used in a survey, it shouldn't be used again. 
Perhaps the only way to do this is through some user developed code, but we would like to know whether the simplest way possible, perhaps it can be done in the qualtrics interface without having to code. We thought this csv file could be somehow uploaded to qualtrics via a contact list and then put into the survey through piped text /embedded data. Perhaps there is a limit as to the size of a file uploaded. We could reduce it, perhaps instead of giving 10 tickets we'd give less, let's say 3 (we are interested in it being more than one because we need to ask respondents whether they want to share tickets with the loser and how many).
Does anyone have any leads/ ideas on how to do this? Thank you!